How do i disable Ctrl + Alt + Del on CentOS 7 / RHEL 7

Control-Alt-Delete is a combination key which initiates the soft reboot of servers; this must be disabled to avoid the un expected and unwanted reboot. In CentOS 6, Ctrl+Alt+Del was handled by inittab; now it is managed by systemd in CentOS 7. This guide will help you to disable Control-Alt-Del keys on CentOS 7.

Let’s look at /etc/inittab file

cat /etc/inittab

Content will look like below.

# inittab is no longer used when using systemd.
#
# ADDING CONFIGURATION HERE WILL HAVE NO EFFECT ON YOUR SYSTEM.
#
# Ctrl-Alt-Delete is handled by /etc/systemd/system/ctrl-alt-del.target
#
# systemd uses 'targets' instead of runlevels. By default, there are two main targets:
#
# multi-user.target: analogous to runlevel 3
# graphical.target: analogous to runlevel 5
#
# To set a default target, run:
#
# ln -sf /lib/systemd/system/<target name>.target /etc/systemd/system/default.target
#

From the above, inittab is no longer handles init function which includes Ctrl-Alt-Delete. Now we have to tell the systemd to disable it.
Use the following command to disable the Ctrl-Alt-Delete.